Product-induced stabilization of tertiary and quaternary structure in Escherichia coli dehydroquinase

The effects of irreversibly attaching product at the active site of type I dehydroquinase from Escherichia coli have been investigated at the level of the secondary, tertiary, and quaternary structure of the protein by spectroscopic and hydrodynamic techniques. The results agree with the previously identified stabilization of the enzyme but show for the first time that the protein dimer is also stabilized and suggest that the E. coli dehydroquinase subunit may be bilobal.